News Intel SSD 665p to Pack 13% More Performance, 50% More Endurance Than 660p

In order to combat this problem, the 665p will introduce the dynamic SLC cache feature. When the drive is at 50%, it'll have a maximum cache of 280GB for the 2TB variant and 140GB for the 1TB variant. Once the SSD breaks the halfway mark, the cache starts to decreases until it reaches a fix amount, which is 24GB for the 2TB model and 12GB for the 1TB model.
This sounds like what the 660p already does. The dynamic cache starts at 140GB for the 1TB model, and works its way down to 12GB when 75% full, and the 2TB model doubles that, with both matching the numbers listed here. I believe the 660p starts reducing its cache around the 25% mark though, so perhaps they adjusted the curve for the new model to maintain more of that cache when a larger portion of the drive is filled.

A $160 MSRP for the 1TB 665p doesn't seem all that attractive when the 1TB 660p has been widely available for under $100 for the last 6 months though. Based on these numbers, the improvements seem quite minor, after all, and probably not worth paying substantially more for.
Nov 26, 2019
I believe other NVMe SSD manufactures offer vastly superior performance and reliability compared to the Intel (QLC)-based SSDs. The Intel 660P was a good deal last year. Now that there have been many price decreases, I would look at brands that offer more than 3000 mbps read and write speeds. This is superb for photo editing and large music file transfers such as 4tb DSD files. There is also a great benefit in speeds from Thunderbolt 3 external NVMe drives on true Thunderbolt 3 ports. Look at Patriot, HP 950, Samsung 970, etc.